package cn.itcast.hotel.service.impl;

import cn.itcast.hotel.mapper.HotelMapper;
import cn.itcast.hotel.pojo.Hotel;
import cn.itcast.hotel.pojo.HotelDoc;
import cn.itcast.hotel.pojo.PageResult;
import cn.itcast.hotel.pojo.RequestParams;
import cn.itcast.hotel.service.IHotelService;
import com.alibaba.fastjson.JSON;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.common.geo.GeoPoint;
import org.elasticsearch.common.unit.DistanceUnit;
import org.elasticsearch.index.query.BoolQueryBuilder;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.index.query.functionscore.FunctionScoreQueryBuilder;
import org.elasticsearch.index.query.functionscore.ScoreFunctionBuilders;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.sort.SortBuilders;
import org.elasticsearch.search.sort.SortOrder;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

@Service
public class HotelService extends ServiceImpl<HotelMapper, Hotel> implements IHotelService {
    @Autowired
    private RestHighLevelClient client;

    @Override
    public PageResult search(RequestParams params) {
        try {
            // 查询数据
            SearchRequest request = new SearchRequest("hotel");
            // 加载请求
            buildBasicQuery(params,request);

            // 分页
            int page = params.getPage();
            int size = params.getSize();
            request.source().from((page-1)*size).size(size);

            // 根据坐标排序
            String location = params.getLocation();
            if(location != null && !"".equals(location)){
                System.out.println("获取到当前位置参数");
                request.source().sort(SortBuilders
                        .geoDistanceSort("location",new GeoPoint(location))
                        .order(SortOrder.ASC)
                        .unit(DistanceUnit.KILOMETERS));
            }

            // 发送请求
            SearchResponse response = client.search(request, RequestOptions.DEFAULT);

            return handleResponse(response);
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
    }

    /**
     * 解析响应
     * @param response 获取es搜索返回值
     * @return 解析后的酒店数据
     */
    private PageResult handleResponse(SearchResponse response){
        SearchHits searchHits = response.getHits();
        long total = searchHits.getTotalHits().value;
        SearchHit[] hits = searchHits.getHits();
        List<HotelDoc> hotels = new ArrayList<>();

        for (SearchHit hit : hits) {
            String json = hit.getSourceAsString();
            HotelDoc hotelDoc = JSON.parseObject(json,HotelDoc.class);

            // 获取排序值
            Object[] sortValues = hit.getSortValues();
            if(sortValues.length>0){
                System.out.println("获取到距离值" + sortValues[0]);
                Object sortValue = sortValues[0];
                hotelDoc.setDistance(sortValue);
            }

            hotels.add(hotelDoc);
        }

        return new PageResult(total,hotels);
    }

    /**
     * 请求参数解析并编辑请求
     * @param params
     * @param request
     */
    private void buildBasicQuery(RequestParams params, SearchRequest request){
        BoolQueryBuilder boolQuery = QueryBuilders.boolQuery();
        // 关键字查询
        String key = params.getKey();
        if(key == null || "".equals(key)){
            boolQuery.must(QueryBuilders.matchAllQuery());
        }else{
            boolQuery.must(QueryBuilders.matchQuery("all",key));
        }
        // 条件筛选
        if(params.getCity() != null && !"".equals(params.getCity())){
            boolQuery.filter(QueryBuilders.termQuery("city",params.getCity()));
        }
        if(params.getBrand() != null && !"".equals(params.getBrand())){
            boolQuery.filter(QueryBuilders.termQuery("brand",params.getBrand()));
        }
        if(params.getStarName() != null && !"".equals(params.getStarName())){
            boolQuery.filter(QueryBuilders.termQuery("starName",params.getStarName()));
        }
        if(params.getMinPrice() != null && params.getMaxPrice() != null){
            boolQuery.filter(QueryBuilders.rangeQuery("price")
                    .gte(params.getMinPrice())
                    .lte(params.getMaxPrice()));
        }

        // 算分控制
//        FunctionScoreQueryBuilder functionScoreQuery =
//                QueryBuilders.functionScoreQuery(
//                        // 原始算分
//                        boolQuery,
//                        // function score的数组
//                        new FunctionScoreQueryBuilder.FilterFunctionBuilder[]{
//                                // 其中一个function score元素
//                                new FunctionScoreQueryBuilder.FilterFunctionBuilder(
//                                        // 过滤条件,满足才会被算分
//                                        QueryBuilders.termQuery("isAD",true),
//                                        // 算分函数
//                                        ScoreFunctionBuilders.weightFactorFunction(10)
//                )
//        });
//        // 装填请求
//        request.source().query(functionScoreQuery);

        // 2.算分控制
        FunctionScoreQueryBuilder functionScoreQuery =
                QueryBuilders.functionScoreQuery(
                        // 原始查询，相关性算分的查询
                        boolQuery,
                        // function score的数组
                        new FunctionScoreQueryBuilder.FilterFunctionBuilder[]{
                                // 其中的一个function score 元素
                                new FunctionScoreQueryBuilder.FilterFunctionBuilder(
                                        // 过滤条件
                                        QueryBuilders.termQuery("isAD", true),
                                        // 算分函数
                                        ScoreFunctionBuilders.weightFactorFunction(10)
                                )
                        });
        request.source().query(functionScoreQuery);
    }
}
